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Fast Algorithm for Tomographic Reconstruction for Plasma Emission

Kotaro YAMASAKI¹⁾, Akihide FUJISAWA^1,2), Yoshihiko NAGASHIMA^1,2) and Shigeru INAGAKI^1,2)

1)

Research Institute for Applied Mechanics, Kyushu University, Kasuga Kohen, Kasuga, Fukuoka 816-8580, Japan

2)

Research Center for Plasma Turbulence, Kyushu University, Kasuga Kohen, Kasuga, Fukuoka 816-8580, Japan

(Received 13 July 2017 / Accepted 4 October 2017 / Published 13 November 2017)

Abstract

Temporal evolution of two dimensional image of plasma emission has been obtained using a reconstruction algorithm called Maximum Likelihood-Expectation Maximization (MLEM), with a tomography system in a linear cylindrical plasma. The calculation of tomography images for the whole plasma duration needs parallel computation due to the iteration processes of MLEM. However, faster and simpler tomography algorithm giving a consistent image with MLEM should be desirable for monitoring the emission profile and quick analysis between shots. This paper proposes such a new algorithm of a modified Tikhonov regularization with introducing a weight matrix, termed here direct matrix reconstruction (DMR).

Copyright (c) 2017 The Japan Society of Plasma Science and Nuclear Fusion Research

Keywords

plasma turbulence, turbulence tomography, MLEM, local emission fluctuation

DOI: 10.1585/pfr.12.1201045

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References

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